Pledged himself to ISIS
Had been under FBI investigation multiple times (just like Ft Hood, Boston, and San Bernadino)
Shouted 'Allah Ackbar'
whose dad was a Taliban supporter/hates gays
regularly beat the crap out of his (ex) wife
was a licensed security guard working for a company contracted w/ DHS
was a registered Democrat
hated gays w/ a passion

killed 50 people and wounded dozens more in a gun free zone.

Obviously the fault of the NRA, Republicans, and the availability of guns.